RTC are you looking for a laptop to take to Ethiopia with you? If so I'd look for durability, battery life, and weight as primary considerations over speed. Shoot for a processor / graphics combo that meets 90% of your needs. Also don't forget universal power adapters. I don't know if you are going to be in an urban area or heading out to very remote places, but a small solar charger may be of benefit. And if you're really heading out in the sticks for long periods of time get a sat phone or even better, a ham radio.
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